Anacapa Island, California
It's hard not to love a hike that begins with a boat trip through whale waters.
Insider's tip: Follow the trail to a 1932 light station, and take in views of Cathedral Cove. Continue to Inspiration Point, where the park's other islands are a must-see.
What's growing: ice plant, giant coreopsis, wild hyacinth
When to go: February–April (Island Packers offers guided tours; islandpackers.com); 805/658-5730 or nps.gov/chis